[Lazarus] TPageControl OnChange calling issue

Michael W. Vogel m-w-vogel at gmx.de
Wed Oct 5 11:37:14 CEST 2016

Am 05.10.2016 um 10:00 schrieb Michael Schnell via Lazarus:
> Maybe an additional property defining the behavior of the appropriate 
> callbacks for all those controls to be "UserAction" "ProgramAction" or 
> "Both", defaulting to the Delphi behavior might be a good idea.
> -Michael
Thats sounds interesting!

A lot of newbies errors rest upon this, I often can see in the forums, 
e.g. endless loops:

TFooControl.OnChange (called by user) -> change TBarControl.Text
TBarControl.OnChange (called by code) -> change TFooControl.Text
TFooControl.OnChange (called by code) -> ...

Of cause, it would be a big job (for all widgetsets), to implement such 
a property (FOnChange is inserted on various class places), but IMHO it 
isn't impossible to do it for useful controls.

But I'm not sure, would such a property be accepted by the Lazarus 

Kind regards


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